Feed mechanism for stapling or like machines



June 10, 1958 C, E, CROQKS ETAL 2,837,743

FEED MECHANISM FOR STAPLING OR LIKE MACHINES' LFE nf Mr/e5 E. 52051165 WL !,iazzz TL. Bec al? b l *f E Z'Zc June 10, 1958 C, E, CROQKS E TAL 2,837,743

FEED MECHANISM FOR STAPLING OR LIKE MACHINES Filed Jan. 4, 1956 Ezrar2 f TS Char/e5 E'. Croc/e5 I WIN/Lam .7i Bea/man l K WM E .E ZLZl E75 @Wim June 10, 1958 C, E, CRQOKS El-AL 2,837,743

FEED MECHANISM FOR STAPLING OR LIKE MACHINES Filed Jan. 4. 1956 3 Sheets-Sheet 3 11 Tm WW2/ VY' l/ 25% y EnDJ-s /zar/es Croc/ 5 Wal/dm eckman f* 2,8374i ICC Patented June 10, 1958 FEED MECHANSM FR STAPLING @R LiKE MACHINES Charles E. Crooks, For; River Grove, and William I. Beckman, Chicago, lil., assignors to Spotnails, inc, Evanston, lll., a corporation of illinois Application Sanuary 4, 1956, Serial Noa S7,393

13 Claims. (Cl. 1-49l The present invention relates to improvements in feed mechanisms for stapling or like machines and is more particularly concerned withsuch mechanisms which are especially useful in industrial or heavy duty types of fastener driving machines of relatively large fastener capacity.

An important object of the present invention is to provide improved feed mechanism for fastener driving machines wherein a series of drivable faste-ning elements is fed successively to a driving plunger.

Another object of the invention is to provide novel feed mechanism for fastener driving machines, which mechanism includes a pusher guide rod with an arm portion returnbent to extend forwardly from the rear of the rnachine, and including improved means for attaching the arm.

A 'further object of the invention is to provide improved means for retaining a pusher guide and pusher spring supporting rod in place with respect to the fastener supply magazine of. a fastener driving machine.

Still another object v.of theV invention is to 4provide improved pusher `guide rod attachment means for fastener ydriving machines adaptedfor ready selective location on the body of the machine in relation to tue length of the magazine portion of the machine.

Yet another object of the invention is to provide improved fastener magazine and feed structurel for fastener driving machines including an improved arrangement of the 'fastener feeding means affording a vmore compact structure.

A still further object of the invention is to provide novel means for controlling -the -limit of feeding travel of a spring biased fastener pusher in fastener driving machines.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description of certain preferred embodiments taken :in conjunction with the accompanying drawings, in which:

Figure l is a side elevational view of a fastener driving machine embodyingy features o'f the invention and with certain parts thereof' broken away and in section to show details-of structure;

Figure 2 is a rear end elevational view of the magazine fof the machine ofFigure l; i

Figure 3i isV a fragmentary sectional elevational detail 'view taken substantially in the plane of 'line Ill-*lli of Figure l; y

Figure 4 is a fragmentary side elevational view of a modification of the machine of Figure l; f

, Figure 5 isa side eleva'tionalview of a modifiedy fastener driving machine showingcertaindetailsof. struct-ure in break-away section;

Figure 6 is 'a fragmentary sectional detail View taken substantially on the line VI-VI' of Figure' 5.;

Figure 7 is a slightly enlarged fragmentary detail sectional elevational viewf taken substantially along the lin-e VII-VH of Figurell; l

Figure-f8? is a: fragmentary det-'ail sectional viewtaken substantially onl the Iline VllI--Vl'llf of Figure 7;

Figure 9 is a side elevational view of the rod-retaining socket bracket; and

Figure 10 is a fragmentary enlarged sectional elevational detail view taken substantially along the line X-X of Figure l.

In Figures l-3, as fastener driving machine 10 is shown which preferably comprises a one-piece body casting including a magazine base portion 11, a handle portion l2 supported upon the forward section of the magazine portion and connected to the rear side of a generally upwardly projecting head section 13 within which is housed fastener driving means (not shown) and which may include a pneumatic cylinder and. piston at the lower end of which is a suitable driving blade which is operable reciprocably in a known manner within agvertical driveway 14 grooved in a front end closure plate 1S secured in suitable fashion as by means of :bolts or screws 17 to the 'front end of the magazine portion 11 under the head 13. Pneumatic huid such as compressed air may vbe supplied to the head 13 through a suitable hose (not shown) 'attached to a fitting 18 on the upper forward portion of the handle 12. Suitable valve mechanism 19 -may be provided for controlling the pneumatic fluid and may be operable by means of a lever 20 located within a hand hole 21 defined between the handle 12 and the magazine portion 11.

According to the present invention, preferred form of fasteners such as generally U-shaped staples are adapted to be supported in substantial supply within the magazine portion 11 of the machine to be fed forwardly into position successively within the driveway 14 for driving therefrom under thrust of the driving blade of the machine into work over or upon which the machine is adapted to be manually placed. To this end, havin-g reference to Figures 2 and 3, the magazine portion 11 is constructed as a hollow generally inverted U-shaped casing providing a longitudinal magazine chamber 22 extending the entire length of the magazine portion `and opening through the front and rear ends respectively thereof as well as preferably also along the bottom of the magazine portion. lt will be observed in Figure 1 that the magazine portion 11 is of substantial length, in the present instance on the order of twice :as long as the handle 12 and with a rear part of the magazine portion 11 projecting substantially rearwardly from the handle, so as to enable the magazine chamber 22 to house a large number of staples in stick form, that is Aadhered together side-by-side in a convenient form to be handled and fed into the magazine from the rear opening into the chamber 22.

Support for the staples within the magazine chamber 22 is alforded by a rail member 23 which extends substantially throughout the length of the chamber 22 and in the present instance comprises a generally inverted U-shaped sheet metal member of a width to `accommodate in free sliding relation thereon a series of sticks of staples.

For attaching the staple track 23 in place, it is provided along its lower or free margins of the side legs thereof with laterally offset marginal attachment flanges 24 arranged to bear against the lower marginal portions of the ins'ideffa-ces defining the chamber 22, as best seen in Fgure 2. It will be observed' that by thus offsetting the marginal attachment flanges adequate spacing is provided above the offsets between the vertical legs or sides of the rail member 23V and the opposing vertical or side walls of the chamber 22 for freely accommodating the legs of staples riding upon the' rail. The top or crown of the rail member 23 is, of course, also adequately spaced from the top Wall defining `the chamber 22 to accommodate the staple crowns in freely' spaced relation from the top of the chamber.

Means for securing the fastener supporting rail member 23 in assembly with the magazine portion il comprise a series of longitudinally spaced transversely extending screws 25 which extend through suitable aligned apertures in the lower margins of the vside walls defining the magazine portion 11 and through the attachment flanges 24 of the rail member. For maintaining proper spacing of the attachment flanges 24 when the screws 25 are drawn up tight, spacer bushings 27 are disposed about the respective screws 25 between the rail marginal flanges 24. Suitable wall thickness in the bushings 27 is provided for while nevertheless enabling minimizing of head roomrrequired for the bushings, by having the opposite ends of the bushings externally chamfered as at 28 so as to lit Well up into the offsetting shoulders between the flanges 24 and the remainder of the side wall legs of the rail 23. Thus, when the screws 25 are drawn up tight, the at least slightly flexible vertical flange or leg or legs of the magazine portion 11 will flex sufficiently to draw in against the flanges 24 of the fastener supporting rail "and draw the same tightly against the opposing ends of the spacer bushings 27, whereby to effect a rigid interconnection of the parts.

At its rear end, the fastener supporting rail 23 is disposed adjacent to the rear extremity of the magazinerportion 11 of the machine. At its'front end, the rail member 23 is provided with a nose projection 29 (Figs. l and 3) Iarranged to extend through a doorway aperture or slot`30 in a backup plate 31 interposed between the front end plate l and the front end of the magazine portion 11 of the machine and cooperating with the plate to provide the driveway 14 within which the driving blade is' guided in its reciprocal driving and return strokes. The construction and arrangement lare such that the front end or tip of the nose 29 lies flush within the plane of the forward face of the doorway and backup plate 31, but does not project forwardly beyond the forward plane of the backup plate. Thereby, the next-to-be-driven staple is supported against driving las the foremost staple is driven from the series or stick of staples carried by the rail member 23. Any tendency of the tips or points of the staple legs to cant rearwardly as the foremost staple isv driven and thus possibly han-g on the lower edge defining the doorway opening 30 is obviated by the provision of a pair of transversely spaced downwardly and forwardly sloping ramp grooves 32 opening into said lower edge in the forward face of the plate 31 and aligned wit-h the side portions of the doorway and thereby with the outer sides of the rail nose 29 so as to be in alignment with the overhanging staple legs.

For feeding the fasteners such asY staples forwardly `along the rail member 23, a generally inverted U-shaped pusher 33 is provided which is dimensioned to freely slidably straddle the rail 23 but with its side legs of a vertical dimension or Width to ride clear above the lower marginal offsetting shoulders of the rail sides or legs. The pusher 33 is engageable behind the series of fasteners on the rail member 23 for biasing the fasteners forwardly in the magazine.

Biasing force for the pusher 33 is supplied by an elongated coiled compression spring 34 carried in freely'slidable relation about a supporting and guide rod 35 which is associated with the pusher 33 in a manner to enable continuous forward thrust of the spring 34 under compression load upon the pusher. To this end, the pusher 33 is provided on one of the side legs thereof, in the present instance the right hand side leg, and more particularly the lower rear end portion of such leg with a longitudinally elongated laterally projecting tubular boss 37, in the present instance constructed as a curled up portion of the pusher side wall, where the pusher is formed from sheet metal, although it will be apparent that if the pusher isy a casting, such boss may be cast integrally therewith. The forward portion of the rod 35 extends freely through the boss 37 and may be provided with a forward end stop collar or nut 38 engageable with the forward end of the side boss 37 to enable retraction of the pusher 33 by retraction of the .rod 35. By preference a thrust washer 39 is engaged against the rear end of the boss 37 for thrusting thereagainst of the forward end of the compression spring 34. Through this arrangement, effective thrust against the boss 37 by the spring 34 biases the pusher 33 continuously forwardly, and the elongated bearing provided by the boss 37 about the rod 35 maintains the pusher 33 against any tendency to cant laterally due to imposition of thrust in a substantially laterally olset manner by the spring 34, thereby avoiding binding of the pusher on the rail member 23.

ln order to accommodate the pusher spring 34 and the rod 35, as well Vas the laterally projecting pusher boss 37, the adjacent side wall of the magazine portion l1 of the machine is provided with a longitudinal Ihollow projection or bulge 4? defining a lateral extension of the magazine chamber 22 and affording a longitudinal pusher spring chamber 41 parallel to the magazine chamber. In the auxiliary or side spring chamber 41, the spring 34 and the rod 35 as well as the means connecting the rod and spring to the pusher are freely longitudinally movably accommodated. It will also be observed that by having the pusher spring chamber at the side of the magazine portion 11, the height of the magazine portion can be maintained at a minimum.

When the magazine of the machine is to be loaded, the pusher 33 is withdrawn from the magazine by withdrawing the rod 35 rearwardly out of the rear open end ofthe chamber 41. After a load of fasteners, in the present instance staples, has been inserted into the magazine, up to about a pusher length from the rear extremity of the magazine, the pusher 33 is inserted into the magazine upon the rail member 23 in forwardly thrusting or pushing or driving relation against the rear extremity of the series of fasteners, and the rod 35 is projected forwardly in the spring chamber 41 to substantially the maximum extent of the rod which carries the front end of the rod into a position spaced a short distance rearwardly from the backup plate 31. In so doing, the spring 34 is placed under substantial compression load against the pusher 33, the spring being anchored upon the rear end portion of the rod 35.

In order to increase the elasticity of the spring 34 by an increase in its length without objectionable projection thereof rearwardly from the magazine portion 11 of the machine, the guide rod 35 is return bent to provide a generally U-shaped loop 42 on its rear end portion with a forwardly directed leg or arm 43 arranged to extend forwardly alongside or over the rear end section of the magazine portion 11. The spring 34 is of sufcient length to encompass not only the main pusher guiding body length portion of the rod but also the loop 42 and the leg 43, under constant compression load against the pusher, with the outer end extremity of the spring thrusting against abutment or thrust lugs 44 adjacent to the distal extremity of the rod arm 43. In the present instance the arm 43 extends forwardly approximately half the length of the main portion of the rod 35.

For retaining the rod 35 in the loaded, service position thereof against the thrust of the compression spring 34, releasable anchoring means are provided, in the present instance comprising a rearwardly extending terminal lug 45 on the distal extremity of the rod leg 43, with a laterally projecting handle or head loop 47 joining the lug to the body portion of the arm 43. Releasably receptive of the lug 45 is a socket bracket 48 (Figs. 1, 2, 9 and 10) secured as by means of a screw 49 to the magazine portion 11 of the machine above the laterally projecting rib-like side wall portion 40 spaced substantially forwardly from the rear end of the magazine portion. Projecting above the magazine portion 11 is a socket kportion 50 on the retaining bracket 48, in the present `instance comprising a curled over upper end portion of the bracket which for this purpose is made from suitable gauge sheet metal. To receive the base or attached end portion of the bracket 48 firmly, the magazine portion fastener inthe series fed fromthe magazine.

In effecting a retained or latched relationship ofthe spring rod relative to the retaining bracket 48, the rod is pushed forwardly against the load? of the compression spring 34, with the handle portion-47 andi the leg 43 swung laterally about the axis of the rod 35 shown in dash position in Fig. 2i'nto a position wherein the latching lug is movable forwardly past` the bracket 48. Then, when the tipof the lug 45'has cleared the forward end of the socket portion of' the retaining bracket, the arm 43 is swung toward the bracket 48 from the dash outline in Figure Z to the full *line position until the lug is engaged against a locating forwardly' projecting laterally opening flange extension 52 of the socket.

When thus located, the lug 45 is guided rearwardly into the socket 50 upon forward manual pressure on the rod being released, so that the spring pressure will snap the rod rearwardly and thus interlock thelug 45V in the socket 50. This interlocked, rod-retaining relationship is maintained throughout the range of travel ofthe pusher 33 by virtue of the constant loading of thev spring 34 which, although it diminishesI inpressure as the supply of fasteners becomes exhausted, nevertheless isv maintained sufficiently to exert a constant rearward thrust upon the rod to maintain the interlocked, retained relationship.

Release of the rod 35 is, ofcourse, easily effected by forward manual pressure upon the' handle 47 'to release thelug 4S from the socket 50',.and` swinging the arm 43 laterally by rotating the rod 35 about its axis, to the right as shown in Figure 2, until the lug45 is clear of the socket 5t). This then enables free rearward move'- mentof the rod 35 for retracting it from the chamber 41 for reloading the magazine, orfor any other reason.

It is highly desirable to avoidprojection of the forward extremity of the pusher 33 into they driveway 14 where the tip or extremity of the pusher wouldbe detrimentally engaged by the driving tip of thedriving'blade. On the other hand, it is important that the pusher maintain feeding pressure engagement With even the last Accordingly, means are'providedfor positivelystopping feed- A ing movement of the' pusher Y 32a-.beyond `perhaps 'a very slight projection into the driveway 14, but only enough to assure rrn pressing of the final` fastener against driveway wall 15. In a convenient form, s uch positive limit stop means comprise a lug o'rboss 53 (Figs. l, 2;.7` and 8) projecting laterally forwardly from,. and from the same leg of the pusher 33 as, the rod bearing'guide loop lug 37. The lug 53rnay be pressed from the material of the pusher. Confronting the lug 53is a fixed stop shoulder 54 provided at the frontend-.of thespring and guide rod chamber 41 on the forward end section of the magazine portion 11 of the'machine'. That is; thestop shoulder 54 faces rearwardly andi islocated to have the stop lug 53 on the pusher engage( the sameas accurately as practicable as the last fastener is driven-,from the machine. Y' j v By preference the stop shoulder 54 is provided in alignment with a laterally opening sightingfopening that opens through the adjacent side of the magaziney portion 11 of the machine and is of large enough size to-perrnit inspection therethrough to determine the load condition of the machine when it is thought by .observation of the expanded condition of the compression spring `34 thatl the machine may need reloading. ,If on looking through the sighting hole 55 fasteners are observedf the workmen Will know that he still has a fair number of fastenersto go before loading. If, howevemon looking through the sighting hole 55 the pusher is .observed the user will know that he must reloady afteronly a few more fasteners have been driven. Furthermore, the sighting hole 55 may be drilled into the side offthe magazine section as an incident to final assembly of the components and after 6 it', been determined exactly the spacing between the tip of the pusher and the adjacent side of the stop lug 53. By drilling the sighting hole 55 properly correlated to such spacing, the stop shoulder 54 can then be accurately predetermined with relation to a forward end wall 57 defining the spring and rod chamber 41.

Since there may be a very slight projection of the tip of the pusher 33 into the -driveway 14, the uppermost portion of the pusher tip is preferably chamfered off as shown at 58. Thereby should the driving blade be motivated in a driving stroke after the last fastener has been driven, the driving blade will cam harmlessly on the charnfer 58 and pushthe tip of the pusher 33 rearwardly out of the way.

It may also be observed that the shoulder 54 serves as a positive stop for the forward extremity of the rod 3S when it is pushed forwardly to its extreme limit incident to latching or unlatching the same relative to the latching bracket socket 5o. This avoids forward overrunning of the latching lug extremity 45 of the rod relative tothe gui-de flange 52 which projects forwardly beyond the extreme forward limit position to which the rod may be pushed incident to the latching or unlatchng thereof.

Where it is preferred to have the rear end section of the magazine portion 11 of the machine shorter than shown in Figure l, it will be desirable to have the interlock or latch mechanism for the pusher rod located correspondingly further forwardly as shown by way of example in Figure 4. ln this arrangement, in order to clear the depending leg portion of the handle 12 the latching bracket 48 Vis mounted on a at faced laterally projecting supporting boss 59 on the bulging chamber rib 4l located at the appropriate distance forwardly from the handle leg. This relationship is also shown by way of example in broken outline on Figure 2. It is desirable to maintain the length of the extension arm 43 of the rod, of a substantially uniform length even though the mainY extent or body portion of the rod located inside of the magazine may have to be shorter to accommodate the shorter magazine.

In the modification of Figures 5 and 6, features of the invention are incorporated in a fastener driving machine 60 including a magazine or base portion 61 including at its forward end portion an upstanding housing structure 62u and on its rear end section or portion upstanding pillar structure 63. In a preferred form the magazine structure or portion 61 of the machine comprises a pair of matching, complementary opposed plate members 64 and 65 secured in face-to-face relation by means of suitable screws 66. Mounted upon the upstanding portions 62 and 63 is a combined head and yhandle member 67 including a forward head portion 68 and a rearwardly directed handle portion 69. The head portion-63 is secured upon the top of the housing portion 62 while the rear end portion of the handle 67 is secured upon the pillar structure 63. In the present instance the machine 60 may be of the pneumatically yoperated type wherein the handle 67 provides an air reservoir supplied from a suitable hose into a fitting 69 at the rear end of the handle or through afitting 7i) above the forward end portion of the handle, the pneumatic fluid being controlled by a valve 71 that is operable through the'medium of a lever 72 directed conveniently into the hand hole afforded below the handle 67.

The magazine portion or structure 61 of the machine has a magazine chamber 73 therein within which a pusher 74 is reciprocably operable to urge fasteners toward the front end of the magazine chamber for driving from a depending nose portion 75 at the front of the machine including a swingably openable gate 77 normally held closed by a yoke type retaining spring 78 snapped in closing relation onto studs 79 at the sides of the forward portion of the magazine section. j p.

A coiled compression spring 89 encircles a guide rod 81 that projects into the magazine chamber and through an upper bearing portion 82 of the pusher. A rear end loop portion 83 of the pusher rod extendsirearwardly .beyond the end of the magazine section 61 and has a forwardly directed arm extension 84 provided with a head end portion 85 including a return bent rearwardly directed latching lug terminal S7.

For latching the rod S1 in service position, the lug 87 kis interlockingly engaged within a latching socket 88 .of a bracket member 89. member 89 is provided with a fiat ear 89a that is en- In this instance the bracket gageable between the side plates 64 and 65 to be secured in'position by one of the securing screws 67. In Figure 6, it will be noted that a forwardly projecting guide lip or flange extension portion 90 is provided on the bracket 89 at the inner side of the front part of the bracket socket 88 for receiving the latching lug 87 and guiding the same in the assembly of the lug with the bracket incident to swinging the arm 84 about the axis of the rod 81 toward the machine for assembly, substantially as described in connection with the pusher rod 35.

Should it be desired to utilize the rod latching4 bracket 89 with a machine in which the magazine portion 61 is longer, the bracket is adapted to be secured between the side plates of the base or magazine portion of the machine rearwardly from the handle pillar structure 63 vrather than forwardly therefrom as shown.

This construction therefore provides a convenient standardized form of retaining or latching bracket.

It will be understood that modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

We claim as our invention:

l. In combination in a machine of the character described, a structure provided with an elongated rearwardly opening fastening element magazine within which a series of fasteners is supported for feeding into position torbe driven at a driving station at the front of the machine, a pusher mechanism for urging the series of fasteners toward said position including a pusher member for engaging the fasteners, a rod on which the pusher member is slidably mounted, said rod having a portion extending into said magazine and a further portion extending rearwardly around the rear end of the machine and forwardly along said magazine and having on its terminal end an interlock lug, and a bracket having an interlock socket within which said lug is latchingly interengageable, said bracket having an attachment flange attached to said magazine, said rod having there- Aabout a compressible coil spring extending from the terminal end portion of said further portion of the rod and into forwardly thrusting engagement with said pusher. v

2. In combination in a machine of the character described, a structure provided with an elongated rearwardly opening fastening element magazine within which a series of fastenersis supported for feeding into position to be driven at a driving` station at the front of the machine, a pusher mechanism for urging the series of fasteners toward said position including a pusher member -for engaging -the fasteners, a rod on which the pusher member isslidably mounted, said rod having a portion extending into said magazine anda further portion extending rearwardly around the rear end of the machine -and forwardly along said magazine and having on its Yterminal end an interlock lug, and a bracket having an interlock socket within which said lug is latchingly interengageable, said bracket having an attachment iiange attached to said magazine, said rod having therebout a compressible coil spring extending from the terminal end portion of said further portion of the rod and into forwardly thrusting engagement with said pusher, said face relation and said bracket flange bein'gsecured between said plates.

f `3.1In combination in a machineV of the character described, a structure provided with an elongated rearwardly opening fastening elementV magazine within which a series offasteners issupported for feeding into position to be driven at a driving station at the front of the machine; a pusher mechanism for urging the series of fasteners toward said position including a pusher member for engaging the fasteners, a rod on which the pusher member is V slidably mounted, said rod having a portion extending into said magazine and a further 'portion extending rearwardly around the rear end of the machine and forwardly along lsaid magazine and having on its terminal end an-interlock lug, and a bracket having an interlock socket within which said lug is latchingly interengageable, said bracket having an attachment flange attached tofsaid magazine, said rod having therebout a coinpr'essible coil spring extending from the terminal end portion of said further portion of the rod and into forwardly thrusting engagement with said pusher, said magazine having externally thereof an attachment surface and said bracket ange being secured to said attachment surface.

4. In combination in a machine of the character described, a structure vprovided with an elongated rearwardly opening fastening element magazine within which a series of fasteners is supported for feeding into position to be driven at a driving station at the front of the machine, a pusher mechanism for urging the series of fasteners toward said .position including a pusher member .for engaging the-fasteners, a rod on which the pusher member is slidablyV mounted, said rod having a portion extending into said magazine and a further portion extending rearwardly around the rear end of the machine and forwardlyl along said magazine and having on its terminal end an interlock lug, and a bracket having an interlock socket Within which said lug is latchingly interengageable, said bracket having an attachment flange attached to said magazine, said rod having thereabout a compressible coil spring extending from the terminal end portion of said furtherportion of the rod and into forwardly thrusting engagement with said pusher, said magazine having externally thereof a laterally projecting lug provided with an attachment surface and said bracket liange being secured to said attachment surface.

5. In combination in a machine of the character described, a structure provided with an elongated rearwardly opening fastening element magazine adapted for delivery of fastening elements to a driving station at the front of the machine, a pusher yfor urging the fastening elements forwardly in the magazine, a rod having a main portion rotatable about its axis and cooperatively related to the pusher and extending rearwardly from the magazine, said rod having a portion extending around from the rear of the magazine and forwardly to a substantial Vextent to provide an arm that is swingable relative to said structure by rotational movement of said main rod portion, biasing coil spring means on said rod portions acting on said pusher to thrust the pusher forwardly, said magazine carrying an interlock bracket thereon -spaced forwardly from the rear end of the magazine about the same distance as said arm projects forwardly, said arm having an interlock lug engageable latchingly with said bracket by manipulation of the rod rotatably and reciprocably, with the springl while acting on the pusher thrusting thel rod rearwardly to maintain latched interengagement of the lug and bracket, and a handle structure on said magazine spaced from said bracket.

6. In combination inA a machine of the character described, a structure provided with an elongated rearwardly Yopening fastening element magazine adapted for delivery vof fasteningelements to a driving station at the front magazine comprising a pair of plates disposed in face-to- 7,5 of the machine, a pusher foriurging the fastening elements forwardly in the magazine, a rod having a main portion rotatable about its axis and cooperatively related to the pusher and extending rearwardly from the magazine, said rod having a portion extending around from the rear of the magazine and forwardly to a substantial extent to provide an arm that is swingable relative to said structure by rotational movement of said main rod portion, biasing coil spring means on said rod portions acting on said pusher to thrust the pusher forwardly, said magazine carrying an interlock bracket thereon spacedV forwardly from the rear end ot the magazine about the same distance as said arm projects forwardly, said arm having an interlock lug'engageable latchingly with said bracket by manipulation of the rod rotatably and reciprocably, with the spring while acting on the pusher thrusting the rod rearwardly to maintain latched interengagement of the lug and bracket, and a handle structure on said magazine spaced from said bracket, said bracket having a lead-in flange thereon for guiding said lug into latching interengagement with the bracket.

7. In aV machine of the character described including a structure provided with an elongated rearwardly opening fastening element magazine adapted for delivery of fastening elements to a driving station at the front of the machine with a pusher in the magazine for urging the fastening elements forwardly in the magazine and a rod having a main portion rotatable about its axis as well as reciprocably movable and the rod being cooperatively related to the pusher 'and extending rearwardly from the magazine with a portion of the rod extending around from the rear of theV magazine and forwardly to a substantial extent and being swingable relative=toA said magazine as well as movable reciprocably by rotational and reciprocal movements of the main rod portion, a biasing spring encompassing the rod portions from a thrust abutment adjacent the extremity of said forwardly extending portion to a thrust abutment against the pusher to drive the pusher forwardly along said main rod portion, a bracket having a forwardly opening socket therein defined at its forward end by a lead-in flange, and means for securing the bracket to the magazine in a position spaced forwardly from the rear end of the magazine about the same distance as said forwardly extending rod portion extends, said forwar-dly extending rod portion having a rearwardly directed latching lug thereon engageable in said socket by movement of the rod rotatably and reciprocably until the lug has engaged said lead-in flange and then engagement of the lug in the socket in response to rearward thrust imposed on the rod by loaded compression condition of the spring thrusting.

against the pusher.

8. A machine as defined in claim 7 wherein said bracket is of sheet metal and the socket and the lead-in liange comprise a curled over extremity portion of the bracket.V

9. In ,a machine as defined in claim 7 wherein the bracket comprises a socketed boss-like enlargement on an ear-like bracket body.

10. In a machine of the character described including a structure provided with an elongated rearwardly opening fastening element magazine adapted for delivery of fastening elements to a driving station at the front of the machine with a pusher in the magazine for urging the fastening elements forwardly in the magazine and a rod having a main portion rotatable about its axis as weil as reciprocably movable and the rod being cooperatively related to the pusher and extending rearwardly from the magazine with a portion of the rod extending around from the rear of the magazine and forwardly to a substantial extent andbeiug swingable relative to said magazine as well as movable reciprocably by rotational and reciprocal movements of the main rod portion, a biasing spring encompassing the rod portions from a thrust abutment adjacent the extremity of said forwardly ex- 10 tending portion to a thrust abutment against the pusher to drive the pusher forwardly along said main rod portion, a bracket having a forwardly opening socket therein defined at its forward end by a lead-in fiange, means for securing the bracket to the lmagazine in a position spaced forwardly from the rear end of the magazine about the same distance as said forwardly extending rod portion extends, said forwardly extending rod portion having a rearwardly directed latching lug thereon en-Y related for engagement of said lug with said lead-in flange by rotational movement of the rod.

l1. In a machine including an elongated fastener magazine structure having a longitudinal chamber therein with an opening at one end for delivering to a fastener driving mechanism, a pusher in said chamber, said magazine structure having an elongated auxiliary chamber parallel to said first mentioned chamber located below the top of said first mentioned chamber and opening into said first mentioned chamber, and pusher biasing means housed within said auxiliary chamber and operatively connected to said pusher.

l2. In a machine including an elongated fastener' magazine structure having a longitudinal chamber therein with an opening at oneend for delivering to a fastener driving mechanism, a pusher in Vsaid chamber, said magazine structure having an elongated auxiliary ychamber parallel to said lirst mentioned chamber located below the top of said first mentioned chamber andV opening into said first mentioned chamber, said auxiliary chamber opening rearwardly of the magazine structure, a guide rod in said auxiliary chamber, a slidable connection between said pusher and said rod, and a biasing spring encircling the rod and engaging the pusher normally to bias the pusher lforwardly in said first mentioned chamber.

13. In a machine including an elongated fastener magazine structure having a longitudinal chamber therein with an opening at one end yfor delivering to a fastener driving mechanism, a pusher in said chamber, said magazine structure having an elongated auxiliary chamber parallel to said first mentioned chamber located below the top of said first mentioned cham-ber and opening into said first mentioned chamber, said auxiliary chamber opening rearwardly of the magazine structure, a guide rod in said auxiliary chamber, a slidable connection between said pusher and said rod, and a biasing spring encircling the rod and engaging the pusher normally to bias the pusher forwardly in said first mentioned chamber, said auxiliary chamber being defined at its forward end by a stop shoulder against which said rod is engageable at its forward tip.

14. In a machine including an elongated fastener magazine structure having a longitudinal chamber therein with an opening at one end for delivering to a fastener driving mechanism, a pusher in said chamber, said magazine structure having an elongated auxiliary chamber parallel to said first mentioned chamber located below the top of said first mentioned chamber and opening into said first mentioned chamber, said auxiliary chamber opening rearwardly of the magazine structure, a guide rod in said auxiliary chamber, a slidable connection between said pusher and said rod, and a biasing spring encircling the rod and engaging the pusher normally to bias the pusher forwardly in said first mentioned charnber, said auxiliary chamber being defined at its forward end by a stop shoulder and said pusher having a stop porhIl tion engageable against said shoulder to determine the forward limit of movement of the pusher.

15. In a machine including an elongated fastener magazine structure having aV longitudinal chamber therein with an opening at one end for delivering to a fastener driving mechanism, a pusher in said chamber, said magazine structure having an elongated auxiliary chamber parallel to said rst mentioned chamber located below the top of said rst mentioned chamber and opening into said rst mentioned chamber, said auxiliary chamber opening rearwardly of the magazine structure, a guide rod in said auxiliary chamber, a slidable connection between said pusher and said rod, and a biasing spring encircling the rod and engaging the pusher normally to bias the pusher forwardly in said first mentioned chaml ber,V said auxiliary chamber being defined at its forward end by a stop shoulder and said pusher having a stop portion engageable against said shoulder to determine the forward limit of movement of the pusher, said magazine structure having a sighting opening thereinto at said stop shoulder and through which opening fasteners or the pusher may be viewed from the outside of said magazine structure when in line of vision opposite said opening.

16. In a machine including an elongated fastener magazine leading to a fastener driving mechanism for delivering fasteners thereto, means within the magazine for guiding fasteners to the fastener driving mechanism, a pusher for biasing the fasteners along the guide means, said pusher including a generally vertically extending leg, a longitudinally elongated bearing portion projecting substantially laterally from one side of said pusher, a guide rod extending through said bearing and on which the bearing is longitudinally slidable, and a biasing spring supported by the rod and thrusting under spring load against said bearing for biasing the pusher toward fasteners in the magazine.

17. In a machine including a staple magazine from which staples are adapted to be delivered to a staple driving station, a staple supporting rail in said magazine, a generally inverted U-shaped pusher slidably ridable on said rail for urging staples forwardly along the rail, said pusher having on one depending leg thereof and substantially below the top of the pusher a laterally projecting longitudinal bearing element, a guide rod extending slidably through said bearing element, and a biasing spring coiled about said rod and thrusting toward said bearing element for biasing the pusher forwardly.

18. In a machine having a magazine portion for supplying fasteners to a fastener driving mechanism, a generally inverted U-shaped elongated magazine housing, a generally inverted U-shape elongated track member having laterally offset longitudinal marginal flanges at the distal margins of the legs thereof, attachment screws securing said marginal anges between the marginal anges of the housing, and tubular spacers engaged about the screws between said marginal flanges and maintaining the marginal anges in spaced relation against draw-up pressure of the screws, said spacers having chamfered ends so as to enable close engagement thereof adjacent to offsetting shoulders between said marginal flanges and the main body portions of said rail legs.

References Cited in the le of this patent UNITED STATES PATENTS 1,630,877 Westin May 31, 1927 1,996,640 Case Apr. 2, 1935 2,463,579 Vail Mar. 8, 1949 2,482,156 Crosby Sept. 20, 1949 2,585,941 Juilfs Feb. 19, 1952 2,714,209 Lindstrom Aug. 2, 1955 

